1. Technical Field of the Invention
This invention relates generally to portable electronic equipment and more particularly to efficient powering of such devices.
2. Description of Related Art
As is known, integrated circuits are used in a wide variety of electronic equipment, including portable, or handheld, devices. Such handheld devices include personal digital assistants (PDA), CD players, MP3 players, DVD players, AM/FM radio, a pager, cellular telephones, computer memory extension (commonly referred to as a thumb drive), etc. Each of these handheld devices include one or more integrated circuits to provide the functionality of the device. For example, a thumb drive may include an integrated circuit for interfacing with a computer (e.g., personal computer, laptop, server, workstation, etc.) via one of the ports of the computer (e.g., Universal Serial Bus, parallel port, etc.) and at least one other memory integrated circuit (e.g., flash memory). As such, when the thumb drive is coupled to a computer, data can be read from and written to the memory of the thumb drive. Accordingly, a user may store personalized information (e.g., presentations, Internet access account information, etc.) on his/her thumb drive and use any computer to access the information.
As another example, an MP3 player may include multiple integrated circuits to support the storage and playback of digitally formatted audio (i.e., formatted in accordance with the MP3 specification). As is known, one integrated circuit may be used for interfacing with a computer, another integrated circuit for generating a power supply voltage, another for processing the storage and/or playback of the digitally formatted audio data, and still another for rendering the playback of the digitally formatted audio data audible.
Integrated circuits have enabled the creation of a plethora of handheld devices, however, to be “wired” in today's electronic world, a person needs to posses multiple handheld devices. For example, one may own a cellular telephone for cellular telephone service, a PDA for scheduling, address book, etc., one or more thumb drives for extended memory functionality, an MP3 player for storage and/or playback of digitally recorded music, a radio, etc. Thus, even though a single handheld device may be relatively small, carrying multiple handheld devices on one's person can become quite burdensome.
A vital concern with every battery powered handheld device is its battery life (i.e., how long the handheld device will run before the battery has to be replaced). There are two primary components to extending the battery life of a handheld device: one is to minimize power consumption and the other is to use the battery to its fullest capacity. Most of the efforts to date with respect to battery life have been focused on reducing power consumption. While this is extremely important, using the battery to its fullest extent is becoming more critical and getting some attention.
Current techniques to use the battery to its fullest extent safely (i.e., shutting down the handheld device in a safe manner when the battery is consumed) monitor the battery voltage. When the battery voltage drops below a threshold, the handheld device is shutdown by storing current user settings et cetera such that when the battery is replaced, the handheld device comes up in a known manner and, if desired, where it left off just before the battery was replaced. If the handheld device is not shutdown in a known manner when the battery voltage drops below the threshold, the software of the handheld device may lock-up causing the handheld device to require service.
While monitoring the battery voltage does provide a safe shutdown mechanism extending the usefulness of a battery, it does not enable the battery to be used to its fullest extent, nor does it distinguish the possible reasons as to why the battery voltage dropped.
Therefore, a need exists for a method and apparatus that maximizes battery life based on operating conditions of a battery powered handheld device.